1. Field of the Invention
This invention pertains to an earth anchor which is screwably embedded into the ground with a power rotating machine generally referred to as a digging machine. The variations in this invention from the prior art reside primarily in the configuration of the anchoring spiral formed from cast iron or other metals having a thick outer edge projecting upward from a point, spiralling from a zero radius to a maximum radius terminating in a trailing taper and trailing point. The configuration of the earth anchor of this invention is such that as the anchor is power driven into the ground by rotation with a digging machine, the anchor, upon contacting stones, force them to the outer circumference as the anchor proceeds to be screwed into the ground. An improved embedding and retention characteristic of the anchor is achieved.
2. Description of Prior Art
Numerous configurations of earth anchors have been developed and patented. These anchors generally comprise auger or screw-type configurations very similar to a propeller. Among the related, previously patented devises are patents such as the one to Black, U.S. Pat. Nos. 2,395,033, which employs two semi-circular members mounted on a shaft in the configuration of a circular propeller. Brown, 2,643,843, which pertains to a sand anchoring device has a pointed shaft with two tilted blades projecting outward in a propeller-like fashion. Perhaps the closest related patent is Sullivan, 3,148,510, which is an earth anchor screwably driven into the ground in a manner very similar to the concept of this invention. The configuration of the Sullivan anchor is essentially a helical, one-turn earth auger. The configuration of the anchoring spiral or wing of the screw earth anchor of this invention differs in its configuration and improved operation and stability when screwed into the ground. The configuration of the anchor of this invention affords an improved and different result when rotatably embedded into the earth.